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By Ian S. Leslie

Seismic monitoring systems for mining operations are being utilized more than ever before in the characterization of rock mass response to underground and open pit mining. This paper provides a review of the use of microseismic monitoring for rock mechanics applications at mines throughout the world. Some practical considerations for the installation of these systems are presented along with techniques for optimizing seismic array coverage. Case studies and installation examples are also provided. Recent applications of advanced seismic analysis techniques are discussed including the determination of event mechanisms, mapping of maximum peak particle velocity (PPV) and seismic hazard fields, and the use of source parameter data for large event re-entry protocol.

Jun 1, 2012

By P. D. P. Hamilton

IT is perhaps obvious to most individuals who are interested in the mining industry that a producing mine has been subjected to several phases of engineering attention. In this paper it is the author's hope that a thoughtful survey of these various engineering phases will emphasize certain points of value and interest which may sometimes be overlooked. The points which we will bring out are being made in an analytical sense and are not in any way a reflection on any individuals or organizations which might see in these illustrations a similarity co chair particular conditions. In other words, we are drawing on our general experience to illustrate the points which we chink are worthy of mention, and which we believe are of a type sufficiently frequent co be emphasized. It is well co point out chat, in this paper, we are not concerned with the relative importance of such theoretical questions as to whether or not a geologisc is more important than a prospector, or the office manager than the surface foreman. We are, however, interested in analyzing the various types of engineering experience required in the bringing of a mining enter-prise from the early prospect stage in co-production, and their importance to the project as a whole. In order to simplify our analysis of the subject, it has seemed best to outline a simple mining organization. In using the terms 'industry' and 'business', we feel chat frequently those engaged in mining do not always appreciate that mining is actually an endeavour, or a business, which has the same economic fundamentals as any other business. In the mining industry, the field and producing engineering are counter-parts of the research and production phases of any other type of business. Once this is realized, it is fairly obvious that mining, like any other industry, is a matter of economically acquiring raw materials, processing them, and finally marketing the resultant commodities as favourably as possible. The points may be discussed in a little more detail as follows.

Jan 1, 1938

By Harry Wilton-Clark

Introduction Coal cleaning may be taken as meaning the separation of coal-as-mined into two or more fractions. Coal cleaning includes coal washing, together with any other means used in the ultimate preparation of coal prior to shipment (as coal) . The method of coal cleaning devised for any given mine must be one which is based entirely on the economic results obtainable. The installation of a high-cost and complex washing plant, designed to produce a low-ash dean coal, at the highest possible recovery, may be unsound practice. A crude 'roughing' washer may be the best result of sound engineering and operating consideration, and in some cases coal cleaning should be confined entirely to preparation at the face. Consideration of complete costs, to the point where the coal is actually sold, may show that certain seams are workable or not workable. Of the seams found workable, extraction of the whole or parts of the seam may be decided on. The portion to be extracted may contain rock or bone partings, which must be removed. It may be good practice to mine the extra portion and remove the objectionable materials by surface washing; or it may be that such materials should be removed underground, even at an increased mining cost. For instance, in some of the steeply pitching seams of the Alberta Crow's Nest Pass district, the removal of bone and rock at the face may be almost impossible under the usual 'up the pitch' or 'angle' mining methods, but possible by mining across the pitch so that the material to be rejected can be removed and gobbed. Again, if a complete seam is being extracted, investigation may show marked differences between top coal and bench coal, and if sufficient mine cars are being loaded from a chute at one time, the fact that such a place is working top or bench coal at the time may be reflected by peaks in ash content or size proportions at the ripple. It may be very effective coal preparation to smooth out such peaks.

Jan 1, 1934

By H. J. McQueen

Pressure welding is a solid state joining technique that depends on bringing the parts into sufficiently close contact that inter-atomic bonds are achieved. Pressing is more effective at elevated temperatures where plastic flow causes the asperities to collapse; improved application conditions are derived from hot-work research to clarify temperature and strain rate dependence of hot strength and ductility. The substructure evolution systematically studied in hot working to determine dynamic recovery or recrystallization is applied to clarifying that developed in welding. The various processes are affected differently by work-piece geometry and final shape requirements. In addition to pre-cleaning of the surfaces, the plastic flow helps disperse the remaining oxide layers as was originally exemplified in blacksmith hot forging of layered sword blades and in bellldie welding of wrought iron tubes. The presentation critically compares the utility for various materials and configurations of simple pressure, ultrasonic application, diffusion, explosive, rotary and linear friction and friction-stir processes. Diffusion bonding (primarily Ti) with light cleaning, low pressure, little distortion in protective furnace atmosphere contrasts strongly with the heavy upsetting in friction welding, or complex alloy mingling and substructure variations in friction stir joints.

Jan 1, 2011

By N. A. Warner

Virtually zero gas emission smelting is promoted as a means for securing environmental advantages and the general public’s acceptance. Concerns about climate change will increasingly make it more difficult for new primary metals projects to come to fruition unless greenhouse gas emissions are decreased. Assuming a sustainable market for sulphuric acid is not locally available, the next best option is high temperature reaction of strong SO2 with limestone or dolomite. This is followed by CO2 liquefaction and disposal either underground or in the deep ocean. The Voisey’s Bay nickel project is cited as an example where appropriate location of a new smelter close to large dolomite or limestone deposits would lead to a virtually zero gas emission operation. Most of the electrical energy required for producing technically pure oxygen and for liquefying CO2 and transporting it to disposal can be derived from smelting a bulk sulphide concentrate and then reacting SO2 at high temperature. Provided the smelter gases are properly cleaned before sulphur fixation, the sulphated stone should be uncontaminated and environmentally benign and possibly of use in the building and construction industry.

Jan 1, 1999

By A. M. Cormie

Introduction The purpose of this paper is to give a brief, general outline of mining practices at Torbrit Silver mine. The geology of the mine is touched on as it is felt that a rough picture of the geology will result in a clearer understanding of the mining methods employed. The main part of the paper deals with mining methods and a section is included on haulage. Development practice is mentioned only briefly. Torbrit Silver Mines, Limited, a subsidiary of Mining Corporation of Canada, is located in the Alice Arm area of northern British Columbia. Access to the mine is by boat to the village of Alice Arm at the head of Alice arm, then truck road, following the course of Kitsault river for 18 miles in a northerly direction to the plant site. The main portal is a further two-thirds of a mile along the course of the river, at approximately the same elevation as the plant, 1,014 feet above sea level. Geology The ore occurs in a massive, irregular-shaped quartz-barite body replacing a folded area in a series of volcanic breccias, tuffs, and flow rocks locally referred to as 'green-stones'. A series of parallel, nearly vertical, fine-grained basic dykes cut across the formation at right angles to the strike of the ore belt over a horizontal distance of 140 feet. The whole of the quartz-barite vein material, which ranges up to several hundred feet wide in places, carries silver values but commercial grade is confined to lenses and shoots where there have been more than usual concentrations of native silver and silver-bearing minerals. The ore-bearing structure plunges at approximately 25 degrees along an axis striking roughly N.65°W.

Jan 1, 1951

By Robert B. Parsons

"The annual onslaught of provincial budgets and tax changes is complete, and once again the Canadian taxpayer is being asked to dig deeper into his pocket to fund old and new programs. It is noteworthy that 1987 tax reform promised lower taxes, but a broader fax base. Five years later, we still have the broader tax base, but the lower faxes have gradually crept up to pre-tax reform levels. Surprise! Surprise!IntroductionThe last edition of Tax Notes commented on some important proposals announced in Manitoba's 1992 budget. In this issue, Tax Notes summarizes the 1992 budget proposals of British Columbia, Ontario and Quebec. These budgets reflect the continuing trend of transferring responsibilities and the related costs-from the federal government to the provinces. As well, the budget papers bear witness to the respective governments' political stripes. British Columbia, Ontario and Quebec are seeking higher tax revenues. Only Quebec continues to acknowledge the importance of the mining industry in its annual budget documents."

Jan 1, 1992

By F. Gaul, H. R. Manouchehri, A. Mosser

"Mining is a major energy intensive industry that contributes in consuming about 7% of the total world’s energy in which almost half in comminution. The underlying trait that drives energy consumption upwards appears to be somewhat persistent due to increasing in population, demands and growth rate. High grade resources have been/being depleted; consequently, low grade, high competent and complex ores with complicated geological structure are brought into perspective. For efficient extraction of values from such resources comprehensive multistage mining and processing strategies must be taken into account. Different treatment technologies, including ore sorting, must be considered to improve resource efficiency and productivity while taking into account the reduction in energy and water consumptions and related sustainability issues.The implementation of sorting technology in mining industry has a long past and its impacts on improving the overall efficiency of both mining and milling have been proven. However, the lack of complete understanding of its potential combined with ore complexity and low capacity of sorting machines have prevented the large scale application in mining industry. The application of X-Ray transmission sorting at Mittersill Tungsten Mine in Austria is presented and discussed herein. A technoeconomic analysis of the technology has revealed a significant potential of adding value to the concentration process. The rough feasibility study has given a strong feed-back on profitability and short time payback of about 2 years for the investment. Except the economic benefits the technology has positive environmental impacts. The potential for saving energy and water is large. The rough calculations have revealed that the energy saving can be up of 840MWh/annum. Furthermore, the ongoing cooperation between Mittersill mine and the sorting manufacturer is a good example on how the development of more competitive products, and product offerings, can be made."

Jan 1, 2016

By E. Asselin

Electrochemical polarization experiments were conducted on alloy 625 in ammonia solution between 25 and 225°C and the results were compared with those of an oxygen solubility model. Results confirm that corrosion is under oxygen control, Normalized corrosion rates are determined based on the rate of oxygen diffusion to the corroding surface, and the corrosion rate at 200°C (-9.7 µA.cm-2) is roughly 24 times higher than the corrosion rate at 25°C (0.4 nA,cm-2), An oxygen-solubility model for Supercritical Water Oxidation (SCWO) conditions was generated using the Redlich¬Kwong-Soave (RKS) equation of state, Results of the model confirm many of the experimental observations from SCWO reactors which suggest that corrosion is at a maximum at temperatures just short of the critical point, The RKS/oxygen diffusion model predicts that the corrosion rate at 365° C is ?85 times higher than the corrosion rate at 25' C. Given that a normalized corrosion rate is obtained, this type of model could be useful for selection of SCWO reactor materials.

Jan 1, 2005

By J. McCreedy

This paper reviews new methods of exploration for metals and new techniques of mining the deposits and extracting the metals from their ores. Examples of mining innovations are taken from Inco's Thompson Operation. The importance of presenting a favorable image of the industry to college students and young people deciding on a career is stressed.

Jan 1, 1971

By Getu F. Biftu

There is general agreement among scientists that global surface temperatures have been increasing during the past decades. The increase in temperature is postulated to be the result of either an increase in greenhouse gases emission or climate variability (i.e., due to variations in sun or volcanic activity or El Nino and La Nina events) during past decades and may continue to increase. The effects of a predicted rise in the Earth?s surface temperature include an increase in average global evaporation and increase or decrease in precipitation (Bloomfield, 1992; Mann et al., 1991; Vinnikov et al., 1990; Gan 1995; Zhang et al., 2000a). The general circulation models (GCMs) project a global warming due to greenhouse effects of 1.5-4.5°C by the mid 2050s, with the most pronounced changes taking place in northern latitudes (Nicholls et al., 1996). However, similar predictions at a watershed scale or even a regional scale using GCMs are mot possible yet (Arnell et. al., 1996; Georgievskii et. al., 1996; Zhang et al., 2000a). Detection of historic trends, changes and variability in climatic variables is another indirect means of understanding potential future changes or variability at regional and local scales. The main objective of this paper is to review studies related to climatic change or variability and associated hydrologic changes at a regional scale and local scale, particularly those studies applicable to the Oil Sands Region (OSR) of Alberta. This paper identifies gaps in our current understanding of the hydrologic processes that may be affected by climate change; it discusses potential implications to developments in the OSR; and it explores mitigation opportunities including several that have already been implemented.

May 1, 2004

By Saba Gharedash

In this study the results of a series of numerical simulations which are conducted for one of the tunnels of the Mashhad metro line 2 project are presented to evaluate the role of tunnel face support pressure and soil strength parameters on deformation of tunnel lining and face deformation. To achieve this goal, comparative numerical simulations of a mechanized tunnel advance in soft non- homogeneous soil on top of the ground water table and beneath the building are conducted and sensitivity analysis is performed. Development of a step by step tunnel construction process is modeled using a three dimensional finite difference model (FLAC3D) taking into account all the relevant components of shield tunneling. In order to understand the mechanism of the effects of a variety of support pressures on face deformation and lining stresses, numerical simulations are conducted. It is found that the use of different face supports causes a considerable influence on the forces of tunnel lining. In addition, it is revealed that building weight help to change the stress paths and the stress distributions in the tunnel lining.

Aug 1, 2013

By M. Maeda, H. Sasaki

"Precious metals such as platinum, palladium, and rhodium are commonly used for automotive catalyst converters. To recover these metals with lower environmental load and cost, exposure to zinc vapor was proposed as a pretreatment prior to acid leaching. Alloying with zinc is expected to enhance dissolution of precious metals and reduce the amount of toxic chemical agents required for the leaching. This study examined the effect of the alloying pretreatment using model catalysts. Catalysts were immersed in leaching solutions for a predefined time with or without zinc vapor pretreatment, and the amount of dissolved metals was then evaluated. INTRODUCTIONAutomotive catalysts account for large portions of the world consumption of platinum (Pt), palladium (Pd), and rhodium (Rh) (Butler, J., 2011). Because of their limited production and high prices, recovery of the precious metals from spent catalysts is obviously an important issue. A representative structure of an automotive catalytic converter can be described as a monolithic ceramic support with a honeycomb structure which is coated with porous oxides such as those of aluminum (Al2O3), cerium (CeO2), and zirconium (ZrO2) (Heck & Farrauto, 2001; Matsumoto & Shinjoh, 2007). Small particles of precious metals, originally several nanometers or less, adhere to the oxides.Typical recovery processes for precious metals from scraps are shown in Figure 1 (a)-(c) (Habashi, 1997; Yoo, 1998; Shibata & Okuda, 2002). Precious metals can be recovered by using non-ferrous smelters as Figure 1 (a) shows. Smelted along with metals such as copper (Cu), precious metals and ceramics in the scraps are absorbed into the metal phase and slag phase, respectively. Because the metals separate from Cu as anode slime in successive electro-refining, such a process can recover precious metals as co-products of Cu. However, in order to prevent negative effects on the principal process, a specialized procedure is needed. Figure 1 (b) is a specialized approach in which scraps are melted at elevated temperature with Cu called the Rose process. Here Cu works as a collector metal, and the absorbed precious metals are then concentrated by oxidation of Cu. Such a process can separate precious metals from ceramics constituting catalyst converters. Smelting at high temperature, however, requires extensive equipment as well as a high amount of energy. On the other hand, hydrometallurgical processes may be effective to separate precious metals from ceramics into an aqueous solution, because chemical agents can act on these metals selectively (Figure 1 (c)). Leaching of precious metals, however, requires strong acid and oxidizing agents because of their corrosion resistance; this makes liquid waste disposal and the large environmental load controversial. To solve the problem, a metal vapor pretreatment was proposed (Okabe, Yamamoto, Kayanuma, & Maeda, 2003a, 2003b; Kayanuma, Okabe, Mitsuda, & Maeda., 2004; Kayanuma, Okabe, & Maeda, 2004; Itoh, Kayanuma, Miyake, Kimura, & Maeda, 2005). A flow diagram of the process using zinc (Zn) vapor is shown by Fig. 1(d). Exposed to Zn vapor, precious metals are expected to form alloys which dissolve more easily than pure precious metals, thus reducing the use of chemical agents and environmental load involved with successive leaching. In previous research (Sasaki, Miyaki, & Maeda, 2010; Sasaki & Maeda, 2010, 2012), dissolutions of precious metal alloys formed by Zn vapor treatment were examined in hydrochloric acid (HCl) using an electrochemical method, and it was confirmed that these metals dissolved at higher rates from the alloys than from their pure states (Figure 2). In this study, the availability of the alloying pretreatment was demonstrated by testing on model catalysts in leaching solutions."

Jan 1, 2012

By J. M. Cooper

The HBMS reverb furnace in Flin Flon was originally designed in the late 1920s. Throughout the decades campaign life has been increased due to operational practices, technological changes and brick quality improvements. In recent decades the campaign life had been extended such that a complete rebuild was scheduled every 3 years. The latest furnace rebuild and start up has been after a campaign life of nearly 6 years. Brick construction methods and techniques along with furnace operational practices allow the present campaign to be double that of the historical campaign length.

Jan 1, 2007

By F. H. Edmunds

Introduction This paper, it is hoped, will serve as an introduction to further work upon the origin of the soils and to a more complete interpretation of the geology of Saskatchewan from a study of the soils of the Province. The great difficulty that is encountered in mapping the structure of the prairie regions of the west must be evident to all who have made the attempt. The rarity of good exposures, due to the extensive coverings of glacial drift, is the greatest obstacle, making it difficult to determine the exact stratigraphical position of such exposures as may be found. In many cases palæontological evidence is lacking, or, if available, our present knowledge of the stratigraphy is insufficient to justify division of the formations into horizons; and until many of these formations have been subjected to petrographic investigation, little can be done in using lithological differences as an aid to the correlation of the usually sparse outcrops met with in the Province. Topography may be of the utmost value as an indication of geological structure when considered in conjunction with other evidence. It does not necessarily follow that, because an area in Saskatchewan has resemblances in surface configuration to an area of oil-producing land in Texas, there is sufficient justification for sinking money in wells without further investigation. Such - investigation should include the study of available soil maps.

Jan 1, 1929

By D. J. MacKinnon

"The Canadian Copper Company, formed in 1885, began mining the nickel-copper ores of Sudbury in 1887 and producing nickel-copper matte from its smelter in 1888(1). Although it was quickly appreciated that the separation of nickel and copper (i.e. refining) was critical to the production of a marketable nickel product, refined nickel was not produced in Canada until about 1918. From the beginning of the industry, there was considerable political agitation to refine nickel in the Province of Ontario(2). The companies, however, claimed that the existing processes, viz. the sodium sulphide ""tops and bottoms"" process operated by the Orford Copper Company of New Jersey, U.S.A.(1,3,4) and the carbonyl process(5,6) developed by the Mond Company at Clydach, Wales, were too costly to operate in Canada. Nickel was first refined in Ontario about 1918 when the International Nickel Company opened a nickel refinery at Port Colborne, Ontario(6). Initially, however, the refinery at Port Colborne employed the Orford sodium sulphide process, and the first electrorefined nickel in Canada was produced in 1920 by the British America Nickel Corporation whose mine and smelter were located in Sudbury, Ontario, but whose electrorefinery was located at Deschenes, Quebec, near Ottawa, Ontario. The purpose of this article is to outline the early history of nickel electrorefining and to trace the significant developments which led to the first successful commercial electrolytic nickel refinery in Canada. The development of an electrolytic process for refining nickel is due largely to the efforts of four individuals, viz. Carl Hoepfner, Hans A. Frasch, D.H. Browne and ultimately N.V. Hybinette, and the contribution of each is discussed separately below."

Jan 1, 1999

By Peter Rubie

For many years, optimising the relining of hard rock grinding mills has been complicated by: ?? the large number of variables; ?? the low frequency of relines (slow feedback loop); ?? the potential economic risk associated with some changes. A technology that has its roots in the automotive manufacturing industry is being utilised to construct a statistically accurate, configurable, and dynamic simulation of the mill relining process. The effects of various mechanisation and process changes can be rapidly modelled and compared. This technology will provide mill maintenance managers and contract relining companies with the opportunity to benchmark current performance against world?s best practice. It will also provide an opportunity for concentrator plant designers and mill manufacturers to plan for maximum plant efficiency, by designing an infrastructure and equipment combination that maximises annual plant availability. This simulation tool and its associated data set, has been developed using recent grinding mill performance data from mills of varying dimensions, liner configurations, mill relining equipment, operator and tool variables. The simulation will provide an output that the various stakeholders can utilise to make optimal decisions within the given financial, physical and technological constraints of the individual concentrator plant.

Jan 1, 2012

By J. Cui, Z. Meng, W. Zhao

"The decomposition of rare earth concentrates containing bastnasite and monazite by alkali solutions has been investigated. A slurry of the rare earth concentrate and the alkali solutions was calcined at different temperatures. The impacts of calcination temperature on the decomposition of rare earth minerals, the oxidation of cerium, the deportment of fluorine and phosphorous, and the adaptability of the method to the different grades of rare earth concentrate were all studied. A possible technique for comprehensive recovery is proposed in which the chemical elements such as rare earth, fluorine, phosphorus, calcium, iron and thorium could be recycled or recovered. INTRODUCTIONThe liquid alkali decomposition method is an important technique for the decomposition of mixed rare earth concentrates. The technique is relatively clean compared with the sulfuric acid roasting method. However, its operation is intermittent rather than continuous. The two-step solid-liquid reaction and the subsequent water washing make it not very suitable for mass production and application. An important reason for the disadvantage is that an additional process of ""calcium removal by acid leaching"" is needed for the technique. The content of calcium in Baotou rare earth concentrates is usually 6-12%. The requirement of the current technique is that the content of calcium should be reduced to about 0.2% after the calcium removal process. Otherwise, the decomposition and leaching of rare earth will be affected. Therefore, calcium removal by acid leaching is a necessity before the alkali decomposition process is carried out. Research on different alkali decomposition techniques has been conducted with prior calcium removal by acid leaching (Xu, 1995; Yu, 1993; Han, Li, Chang, Liu & Xu, 1985). There have been some investigations of direct decomposition of the bastnasite (Feng, Pan & Li, 1998; Zhao, Zhang, Yang & Liu, 2002)and monazite (Sun, Li, Li, Su, Zhao & Liu, 1998; Zhou, 2005) by alkali-liquid, however, all studies were carried out in solid-liquid reaction system, and continuous calcination studies have not been reported.This paper investigates the process of direct decomposition of Baotou rare earth concentrates by continuous calcination with concentrated alkali. Using the rotary tubular electric furnace, the mixture of rare earth concentrate and concentrated alkali solution were decomposed continuously. Satisfactory decomposition results were achieved. A method for clean processing and comprehensive resource recovery from Baotou rare earth concentrates is proposed."

Jan 1, 2012

"RÉSUMÉOn discute les principales sources de dilution au cours d’une exploitation souterraine. Les différentes définitions de la dilution en usage sont analysées. Une nouvelle méthodologie de calcul simplifiée et facile à utiliser dans la pratique minière est présentée. Cette méthodologie permet de remplacer les différentes expressions analytiques en usage par les deux facteurs de dilution seulement : un «facteur de dilution planifiée» lié à la sélectivité d’abattage au niveau de la planification minière et un «facteur de dilution additionnelle » permettant de juger de l’efficacité du contrôle de terrain et de la dilution pendant l’exploitation souterraine. L’application de cette méthodologie donnerait un outil nécessaire aux niveaux de la planification, du suivi des travaux d’exploitation et d’éventuelles études comparatives des coûts entre les différentes situations minières.ABSTRACTThe principal sources of dilution during underground evaluation and mining are discussed, then definitions of ore dilution currently in use are analyzed. These definitions vary depending on the authors. A new ore dilution evaluation methodology is proposed, replacing the ten different analytical expressions by only two: the planned dilution factor related to the stoping selectivity, done at the mine planning level, and the additional dilution factor related to the efficiency of the dilution control measures during stoping operations. The conclusion shows that the use of this methodology would be a definitive asset in planning, in stoping operations follow-up, and in future costs comparison studies between mining operations."

Jan 1, 2001

By H. J. Rowley

THERE are many varieties of limestone, but for the general purposes of the pulp and paper industry, two classifications are sufficient: (1) High-calcium stone, which should be quite free from impurities and contain not less then 90 per cent calcium carbonate. (2) High-magnesium stone, containing not less than 25 per cent of magnesium carbonate. Before proceeding with detail on the use of limestone and lime in the industry, a few words regarding the pulp products made in Canada are desirable. By far the largest tonnage is made by grinding spruce and balsam logs on rotating sandstones or on artificial abrasive stones of the Norton or Carborundum types. This mechanical or groundwood pulp finds its largest use in the production of newsprint paper, of which it comprises about 80 per cent of the total fibrous substance employed-the remaining 20 per cent being unbleached sulphite pulp. No limestone or lime is directly employed in making groundwood pulp, as contrasted with the chemically prepared pulps, all of which require one or the other form of the base for their processing. Sulphite pulps comprise the next largest tonnage group. They are produced by boiling, under pressure and at elevated temperatures, spruce and balsam wood in chip form in solutions of bisulphites and sulphurous acid. The usual bisulphites employed are those of calcium and magnesium. Sodium, potassium, and ammonium bisulphites give progressively better pulps, but to date, in the absence of efficient recovery methods, cost has precluded their use.

Jan 1, 1939